论文部分内容阅读
材材线虫(Bursaphelenchus xylophilus)是引起日本当地松树的一种严重病害。近来,美国曾有人认为线虫是一种病原。病理学家们也曾推测这种病原会威胁这里的森林。然而迄今尚未确证松材线虫能否使生长在林中的乡土树种北美松致死。但却有迹象表明,线虫能造成生长在美国的一些外来松树苏格兰松(Pinus sylvestris)和日本黑松(P·thunbergii)死亡。媒介昆虫在产卵时将线虫传播于伐倒木及濒死木,使线虫在濒死木上生存下来,而它们却不是致死树木的主要原因。最近在美国发现的关于线虫与受威胁林木有联系的现象,可以用媒介昆虫产卵期间线虫的迁入来解释。
Bursaphelenchus xylophilus is a serious disease that causes pine trees in Japan. Recently, some people in the United States considered nematodes as a pathogen. Pathologists have also speculated that this pathogen will threaten the forest here. However, it has not been confirmed to date whether pine wood nematodes may cause the death of North American pine, a native species that grows in the forest. However, there are indications that nematodes can cause the death of some exotic Pinus sylvestris and P. thunbergii grown in the United States. Insects disseminated nematodes at the time of spawning on fallen logs and near-dead wood, leaving the nematodes to survive on the verge of dead wood, which are not the main cause of lethal trees. The recent discovery in the United States that nematodes are linked to threatened trees can be explained by the immigration of nematodes during oviposition of vector insects.